1. Technical Field
The present invention relates to liquid ejecting apparatuses and image forming methods.
2. Related Art
As one example of liquid ejecting apparatuses, there are known Inkjet printers that carry out printing by ejecting liquid (ink) onto a medium such as paper, cloth, and film. These printers are provided with a head in which a plurality of nozzles for ejecting liquid onto a medium are lined up in a first direction (sub-scanning direction), and this head ejects the liquid while moving in a second direction (main scanning direction) that intersects the first direction.
From a viewpoint of increasing picture quality, the above-mentioned printer may for example carry out so-called overlap printing or interlaced printing. That is, the printer moves the head a plurality of times alternately in the second direction and the first direction, and forms a plurality of raster lines, to form an image (see International Publication WO 01/03930).
In this regard, from a viewpoint of increasing the speed of printing, some of these printers are provided with a head unit that has a plurality of the heads arranged along the first direction. In this case, it is conceivable for example that a width of the head unit in the first direction is set wider than a width of the medium in the first direction in such a manner as liquid is ejected at one time across an entire width region of the medium. However, with this configuration, in the case where the total movement amount of the head unit in the first direction during printing is large, it is necessary to increase the first direction width of the head unit in order to eject the liquid at one time across the entire width region of the medium during movement in the second direction.
Furthermore, it is known that ejection characteristics of liquids vary due to individual differences of the heads. For example, one head may have a characteristic of ejecting liquid easily, while another head may have a characteristic of ejecting liquid with difficulty. For this reason, in the case where the plurality of heads that constitute the head unit are to eject liquid, so-called density irregularities or the like may occur due to differences in the ejection characteristics of each of the heads, and as a result, there is a risk that image quality will deteriorate.